1. Field of the Invention
This invention relates generally to knowledge engineering systems, and more particularly to a knowledge engineering tool which receives a batch of information (or data) and processes it to reach a conclusion according to one of a plurality of sets of rules.
2. Prior Art
Knowledge systems or expert systems are data processing systems that imitate human expertise and reasoning by using an inference engine and a plurality of stored rules which have been developed as a result of human experience. As a result of this knowledge system or expert system, the experience that a knowledgeable person has developed over a period of time can be made available to others, without requiring that individual to be personally available. Various types of expert systems have been known and used in the past.
Such expert systems have been described and discussed in various publications previously. One version of such expert system has been detailed in U.S. Pat. No. 4,648,044 to Hardy and Joyce and assigned to Teknowledge. Another expert system has been described in prior art U.S. Pat. No. 4,827,418 to Gerstenfeld and assigned to UFA Incorporated. A further expert system or knowledge based processing application was described in U.S. Pat. No. 4,783,752 to Kaplan et al. and assigned to Teknowledge. As yet another example of prior art, U.S. Pat. No. 4,713,775 to Scott et al. describes a problem solving system using a knowledge data base and an inference engine.
The foregoing patents describe various approaches to storing and using the expertise that individuals have developed over time in a computer environment that is, an inference engine with a plurality of rules to develop a response which simulates that of a human expert in a particular field.
The fields to which expert systems have been applied very significantly. One such field is the selection of maintenance functions, particularly preventive maintenance, on complex equipment. For example, in the field of electromechanical document processors, a significant number of mechanical and electromechanical elements work together to move checks and other documents at high speed along a predetermined path, reading information from the check, and sorting it into a desired bin or pocket. The speeds at which these checks travel, up to twenty miles per hour, and the variations in the check size and condition, require a system which is both flexible and resilient. This machine is made up of thousands of parts which wear at different rates, age in different ways and interact with one another in varying ways to produce complex and changing maintenance situations. Preventive maintenance attempts to predict which parts are likely to fail and allow their replacement before failure disrupts production.
Historically, the maintenance of these machines was somewhat of a "black art". An individual mechanic working on such system would develop various specialized understanding (and almost intuition) about the machinery and its future operation, allowing him to perform effective maintenance, even preventive maintenance, which allowed the system to operate efficiently.
Each installation of equipment provides a unique environment in o which the equipment is operated. Some installations prefer - or even require - that the equipment be removed from service for only a short period of time at any given time. This requirement implies that the maintenance must be planned for relatively short downtime. That is, that preventive maintenance must be done within the time constraints which will most improve the operation of the machinery if the user will not tolerate an extended operational delay or a reduced production level due to ineffective or unproductive maintenance.
Recently issued U.S. Pat. No. 4,884,217 describes an expert system with multiple classes of rules such as retrieval rules, analysis rules and action rules, but these sets of rules appear to be applied sequentially rather than one set selected for a given key factor or set of key factors.
Other users designate a given machine for processing documents of poor quality which are expected to have increased feeding problems or create jams and other problems which require frequent maintenance and impose other constraints on maintenance. Accordingly, the maintenance of complex equipment presents situations which require drawing on backgrounds having a significant expertise. Since this expertise cannot be created instantly, there is a requirement for an apparatus which can simulate the thought process of an expert by using an inference engine and a plurality of sets of stored rules, and a selection process in which one of the sets can be selected.